How to Grow Vegetables Year-round in a Greenhouse

Polythene tunnel as a plastic greenhouse in an allotment with growing vegetables at sunset.

If you love to garden every summer and hate when it ends, then you should consider building or purchasing a greenhouse. This way you can eat fresh vegetables all year long, make your own canned items, and save some cash. A greenhouse however, is no small task to upkeep. It takes time and patience to get in a routine of caring for your plants all year long. If you’re tired of paying premium prices for organic fruits, vegetables, and herbs a greenhouse is the way to go. Start small, and in time you’ll save a ton of money a year on food.

Greenhouse Kit Cost

Initially, with any project, it can be costly. The largest cost is the kit you purchase or the materials you use to build your greenhouse. If you or your spouse is handy you can repurpose items you may already have, to build a greenhouse. Most greenhouse kits under $600 are going to be fairly simple in design and may not be the best option if you live in an area that experiences potential hazards such as strong winds, torrential downpours, or power outages. With changing weather, it is best to buy or building something that is going to last.

Aside from the structure, you’ll need a cart or two, some shelving, plants – already started or seeds, a storage container, soil, grow lights (optional), solar panel kit (optional), and other tools as you see fit. Starting a greenhouse could cost anywhere from $400 to the high thousands, depending on the size.

Picking the Right Size

four collage image of different styles of outdoor greenhouses. One is glass, one is wood, one is canvas , and the last one is a combination of plastic and metal

The market is flooded with greenhouse starter building options. It can be a task to select the right one and you certainly don’t want to overload yourself with your first greenhouse. Smaller units may consist of two or three shelves and have plastic liners that you can zip around to open and walk inside. They typically come with UV coded polycarbonate panels and have vents. They are durable and the UV panels allow for sunlight diffusion, while the vents assist with climate control and air circulation.

To better understand what size you need, you need to know how many plants and what kinds you’ll be growing throughout the year. Small greenhouses that are 4’ X 6’ are great for growing herbs, but not many vegetables. If you want constant vegetables throughout the year a 10’ x 12’ greenhouse is a manageable size for your first attempt at greenhouse plants. Remember, if you’re planting vegetables that grow fairly tall you want to make sure you have plenty of room. You may need more area for proper shelving to house all of the vegetables you want.

Greenhouse Site Area On Your Property

Glass greenhouse in garden Summer in garden lush green

You’ll want to keep your greenhouse close to your home to make your routine go faster. Keep it close to a water source as well – not everyone is on a well or will have a water source inside their greenhouse. Make sure to obtain the proper permits to build a greenhouse on your property. HOA’s could also be an issue, but even without one, check your local zoning laws to be sure.

Your greenhouse will need the maximum exposure to sunlight or at least six hours a day of sunshine. If natural sunlight is not an option, you’ll need to consider acquiring grow lights and solar panels.

Understanding Greenhouse Kits

A white pvc and canvas greenhouse with the door open and a small wooden table filled with plants and garden tools on the inside

A kit doesn’t always come with everything. Typically greenhouse kits are just the shells and you may have to purchase other material to secure the greenhouse to the ground. Make sure you understand what you are buying, do some research, and gather the right information. You don’t want to waste your money buying something that’s too small or too big.

Heating and Cooling for Your Greenhouse

Row of blue and black solar panels reflecting the sunlight off of the bottom left corner

Most of us love tomatoes and squash in the summer, but are you up for growing them in a greenhouse during the winter? There are kinds of vegetables and variations that you could try. To prepare for winter gardening be sure to consider these things:

Understand the climate in your area so your veggies don’t die during the winter
Understand the temperatures certain veggies need
Have insulation ready, for colder days
Solar panels

Grow lights
Use heaters
Get a thermostat
Ventilation for air circulation
Raise plants off the ground

Heating

Heat is essential for all greenhouses. If you don’t have heat or proper insulation you may run the risk of losing your crop. Most contractors will provide you with a free estimate for their services, should you decide to run utilities out to your new greenhouse.

Solar kits are sold for greenhouses and can be costly at first, but you won’t have an electric bill once installed and you’ll never have outages. Some plants do better in winter than others, for those that don’t, make sure you have grow lights.

Cooling

During summer months you’ll need to increase ventilation and will probably need fans. If you decided to go solar you can power special greenhouse fans this way. You can also get special shades to help lower the temperature inside the greenhouse. Most of the smaller greenhouses have one or two large vents or windows you can prop open.

Consider specialty fans
Oscillating fans

UV Shades
Temperature gauge

Pest Control

Close up view of vegetable leaves with chew holes from pests

Plants and pests come hand in hand. To stay green and more organic, use natural pest products. Always clean and straighten your greenhouse. Always check plants before bringing clippings from herbs and fresh veggies into your home. Keep tools you use in the garden and greenhouse clean.

Vegetables That Do Well in a Greenhouse

A variety of vegetables including tomatoes, broccoli, cauliflower, cabbage and lettuce

There are a ton of great vegetables you could plant in a greenhouse. The best picks are ones with longer grow times and do better in cooler seasons. Always do research on your favorites to see if they work well. Understand the environments needed, temperatures, and humidity levels in your area so you know what will thrive best.

Starting out, go slow and select only a few. You want your first experience with a greenhouse to go well. Then you can expand in the following years. Make sure you have the appropriate height and space inside for the different plants you select. You can always hang plants for more space.

Best Long Grow Time Plants:

Tomatoes
Peas
Artichokes
Kale

Broccoli
Cauliflower
Collard Greens
Arugula

If you’re able to grow your own vegetables all year long you will gain in two large aspects of your life. You will save money and have healthier food options. These will positively affect your family and the well-being of your future. The majority of store bought foods contain unwanted chemicals as well as other preservatives. Running your own greenhouse will prove to be a great learning experience that you can build upon.